Spatial Distribution of Medusa and Frequency of Parasitic Association with (Cnidaria: Hydrozoa: Trachylina) in Temperate Southwestern Atlantic Waters.

This study examined the spatial distribution of the medusae phase of (Narcomedusae) in temperate Southwestern Atlantic waters using a total of 3,288 zooplankton lots collected along the Uruguayan and Argentine waters (34-56°S), which were placed in the Medusae collection of the Universidad Nacional de Mar del Plata, Argentina. In addition, we reported the peculiar parasitic association between two hydrozoan species: the polypoid phase (stolon and medusoid buds) of (parasite) and the free-swimming medusa of (Limnomedusae) (host) over a one-year sampling period (February 2014 to March 2015) in the coasts of Mar del Plata, Argentina. We examined the seasonality, prevalence, and intensity of parasitic infection.

Checklist of Benthic Cnidaria in the SW Atlantic Ocean (54ºS-56ºS).

In this study we provide an updated checklist of benthic Cnidaria from SW Atlantic Ocean that comprised the Marine Protected Areas Namuncurá I and II, located at Burdwood bank, and other neighbouring locations. A total of 88 taxa was recorded: 36 hydrozoans and 52 anthozoans from which 32 were octocorals, 10 scleractinian corals, 8 sea anemones and 2 zoanthids. Burdwood bank presented the highest richness considering that 87% of the recorded species inhabit this plateau or its slope.

Correction: Macroscale abundance patterns of hydromedusae in the temperate Southwestern Atlantic (27°-56° S).

[This corrects the article DOI: 10.1371/journal.pone.

Macroscale abundance patterns of hydromedusae in the temperate Southwestern Atlantic (27°-56° S).

Gelatinous organisms are crucial components of marine ecosystems and some species imply social and economic consequences. However, certain geographic areas, such as the temperate Southwestern Atlantic (SWA, 27° - 56° S), remain understudied in terms of jellyfish ecological data. We analyzed 3,727 plankton samples collected along ~6.

Census of Cnidaria (Medusozoa) and Ctenophora from South American marine waters.

We have compiled available records in the literature for medusozoan cnidarians and ctenophores of South America. New records of species are also included. Each entry (i.

Areas of endemism in the Southwestern Atlantic Ocean based on the distribution of benthic hydroids (Cnidaria: Hydrozoa).

Geographic distributions of 130 species of benthic hydroids were used to infer areas of endemism in the Southwestern Atlantic Ocean (SWAO, between 22°S and 55°S). Endemicity Analysis (EA) was carried out with the software NDM VNDM, using a 2° x 2° grid with different values of F (F = 0.5 and F = 1.

Reassessment of morphological diagnostic characters and species boundaries requires taxonomical changes for the genus orthopyxis L. Agassiz, 1862 (campanulariidae, hydrozoa) and some related campanulariids.

The genus Orthopyxis is widely known for its morphological variability, making species identification particularly difficult. A number of nominal species have been recorded in the southwestern Atlantic, although most of these records are doubtful. The goal of this study was to infer species boundaries in the genus Orthopyxis from the southwestern Atlantic using an integrative approach.

Marine fouling invasions in ports of Patagonia (Argentina) with implications for legislation and monitoring programs.

Ports are a key factor in the understanding and solving of most problems associated with marine invasive species across regional and global scales. Yet many regions with active ports remain understudied. The aim of this work was to (a) identify and quantify the marine fouling organisms in all Patagonian ports of Argentina classifying them as native, exotic or cryptogenic species through a rapid assessment survey and experimental studies, (b) survey the environmental and anthropogenic variables of these ports and (c) analyze and discuss these results in the light of the South America context for the study of marine invasive species, legislation and commerce.

A comparative study of populations of Ectopleura crocea and Ectopleura ralphi (Hydrozoa, Tubulariidae) from the Southwestern Atlantic Ocean.

Ectopleura crocea (L. Agassiz, 1862) and Ectopleura ralphi (Bale, 1884) are two of the nominal tubulariid species recorded for the Southwestern Atlantic Ocean (SWAO), presumably with wide but disjunct geographical ranges and similar morphologies. Our goal is to bring together data from morphology, histology, morphometry, cnidome, and molecules (COI and ITS1+5.

New C-secosteroids from the gorgonian Tripalea clavaria.

Seven new C-secosteroids were isolated from the gorgonian Tripalea clavaria collected from the South Atlantic. These compounds have a Delta(5), 9,11-secosteroid nucleus together with a 22S hydroxyl group. The absolute configuration of the 22-hydroxyl group was determined with the help of COSY spectra of the Mosher esters of the compounds.

Two new records of Pycnogonids on the Uruguayan coast.

The Pycnogonida from Uruguayan waters are scarcely known, and their reports are markedly discontinuous. In this paper, several individuals of two previously unrecorded Pycnogonids at the shallow rocky subtidal and lower intertidal fringes of Cerro Verde (Rocha, Uruguay) are reported. The specimens were assigned to Pycnogonum pamphorum Marcus, 1940 and Anoplodactylus petiolatus (Kroyer, 1844).